Gather supporting evidence for your competency contest. Contact the physician who cared for the testator at the time the will was executed; you must prove the testator's mental state at the time of the will's execution in New Jersey. Ask the physician about the testator's mental state. Request copies of medical records.
Collect evidence of your undue influence challenge. Search the testator's home for correspondence or other evidence of the relationship between the testator and the person you are alleging coerced or pressured the testator in making his will.
Make a list of persons you believe can offer information to support your case. New Jersey law permits witness testimony at the contest trial. Contact each witness and verify the information. Tell the witness you are pursuing the case in court so he is prepared.
Visit the New Jersey Surrogate Court clerk's office where the will is being offered for probate. Ask for the complaint form to initiate a will contest and court instructions. Fill out the complaint in full. Detail your reason for the contest. File the complaint with the court clerk. Take the stamped copy of the complaint from the clerk.
Serve notice of the complaint on all interested parties, as required under New Jersey law. You must serve all persons with an interest in the state, like heirs and beneficiaries, the executor and the estate's attorney. Contact the court to determine if the parties must be personally served or if you can mail the notice by certified mail, return receipt requested. File proofs of service with the court.
Attend mediation with the estate's representatives. New Jersey typically recommends mediation for both parties to try and resolve the issue prior to trial. You will be notified of the mediation date and time by mail. Make a list of events that support your contest to prepare yourself.
Inform all of your witnesses of the date and time of the trial if mediation does not work. Your witnesses must attend the trial to testify on your behalf.
Comply with all court requests. Attend your hearing on the date and time set by the court. Bring your original evidence with you.